Display devices generally have a display panel in which a switching element substrate and an opposite substrate are bonded together to hold a display medium layer in between. In this configuration, the amount of light transmission is controlled by the difference in potential between the pixel electrode formed on the switching element substrate and the common electrode formed on the opposite substrate, and an image of particular gradations is displayed on a display screen accordingly.
In recent years, as switching element substrates, active matrix substrates having switching elements arranged in a matrix for respective pixels have widely been in use. These active matrix substrates generally have multiple connection terminals, which are arranged in parallel with each other and are respectively electrically connected to the switching elements for sending drive signals to the respective switching elements. Patent Documents 1 and 2 disclose structures adjacent to the connection terminals on active matrix substrates and manufacturing methods therefor.